#include <stdio.h>  
  
int main() {  
    int n, count( );  
    scanf("%d", &n);  
    printf("%d\n", count (n, n - 1));  
    return 0;  
}  
  
int count(int n, int m) {  
    if (n < 1 || m < 1)  
        return 0;  
    if (n == 1 || m == 1)  
        return 1;  
    if (n < m)  
        return count(n, n);  
    if (n == m)  
        return count(n, m - 1) + 1;  
    return count(n - m, m) + count(n, m - 1);  
}  